Flexible conduit.



No. 825,227. PATENTED JULY 3, 1906. G. A. LUTZ & G. G. SIBLEY.

FLEXIBLE CONDUIT.

urucmron FILED MAR.14.1905.

UNITED STATES PATENT 0B FIGE.

GEORGE A. LUTZ, OF NEW YORK, N. Y., AND CLARENCE C. SIBLEY, OF

PERTH AMBOY, NEW JERSEY.

FLEXIBLE CONDUIT.

Specification of Letters Patent.

Patented July 3, 1906.

Application filed March 14, 1905. semi No- 260,653.

To all whpmjt may concern:

Be it knownthat we, GEoRGE'A. LUTz, re-

siding in'New York city, borough of Brooklyn, New York, and CLARENCE C. SIBLEY,residing in Perth Amboy, Middlesex county, New Jersey,citizens of the United States, have invented certain new and useful Im rovements in Flexible Conduits, of which t e following is a specification.

Our invention relates to improvements in the class of flexible conduits which have an insulating paper tube or lining inclosed within a fabric cover, usually woven or braided thereon, within which conduit an electric wire or conductor is to be placed. In installing such conduits workmen frequentl find the wire to be inserted too large to read ily enter the bore of the tube or lining, and they remove such paper tube or lining by pulling the same from its fabric cover, which ma terially reduces the insulating qualities of the conduit with consequent risk and danger.

The object of our invention is to prevent the pa er tube or lining in such class of conduits ffom being readily removed from the outer cover, to thereby prevent the use of the conduit without having the tube or paper lining therein, and in carrying out our invention we weaken the paper tube or its convolutions at any desired number of places, preferably by cutting slits in the paper from edge to edge, whereby if a workman attempts to withdraw the paper tube or lining from the outer cover the paper will readily tear near or close to the end of the conduit, the rest of the paper remaining in the conduit.

Reference is to be had to the accompanying drawings, forming part hereof, wherein Figure 1 is a partlybroken side view of a piece of flexible conduit embodying 'our invention. Fig. 2 is a cross-section on the line 2 2 in Fig. 1. Fig. 3 is a cross-section on the line 3 3 in Fig. 1 through the inner tube or lining of the conduit, the wall of the weakened part being opened out to disclose the construction. Fig. 4 is a perspective view of a portion of the tube or lining, showing the manner of weakening the wal s of the same; and Fi s. 5 and 6 are details of modifications.

. Sirni ar numerals of reference indicate corresponding arts in the several views.

The con uit shown in the accompanying drawings is mainly of well-known class, aving a spirally-wound paper tube or lining 1 and a cover 2 braided, woven, or otherwise applied thereon, all of which may be rendered fireproof or waterproof by suitable treatment in any well-known manner.

The strip of paper or other insulating material from which the tube or lining 1 is made is weakened in different places at suitable distances apart by reducing the thickness of the paper, and this may be done by cutting into the paper at 1, preferablyfrom its outer surface toward its inner surface, in a direction at an angle to or transversely of its length, whereby tongues or laps 1 are formed, said tongues being referably left upon and inte ral with the b0 y of the paper, so as to be lai back over the cut or slit 1" to assist in retaining substantially the normal thickness of the wall of the paper and providing a finished surface over the weakened parts 1, upon which the fabric 2 is applied. The cuts or weakened places 1 may be made in the paper strip by any suitable tool just as the paper is beingwound u on a mandrel, or the slits could be made in t e paper after the s irally-wound lining orcore is made. In either case the covering 2 will be applied upon the tube 1 after the walls are weakened, and the threads or fabric of the core will hold the tongues 1 securely down upon the main body ortion of the inner tube 1.

In ig. 6 the paper strip is indicatedas weakened by a cut 1' on its inner surface, which cuts may be at suitable distances apart, and in Fig. 5 the aper strip has cuts 1 in its edges, whereby t e strip is weakened.

The arrangement above described is such that the flexible tube may be used in wellknown manner for receiving electric wires; but if a workman should desire to remove the tube or lining 1 from the cover 2 by attempting to pull the tube through the end of the cover such tube would tear at one of the weakened places 1*, and the workman could then remove but a small portion of the tube, and at each further attempt to remove the tube from the cover 2 but a small piece could be pulled out, the cover 2 closely and firmly gri ping the tube 1.

t will be obvious that the walls of the tube 1 can be weakened without cutting into the same in the precise direction or at the exact angle shown in the drawings and that a substantially similar weakeni the tube may be made by ines of perforaof the walls of tions acress tlie same at suitable distances a a, tubegformed of aspirally-woundstrip ofiine apart instead of cuts shown.

In ounappIlicatiomf'or patent filedcA rill3, 1906, Seria 0. 309,605, we havespecigcally claimed a conduit in which the walls of the tube are weakened by perforations v gr Having now described our invention, what e c a m: l a r 1. A, conduit for electric wires an inner tube made of a spirally-wound'strip of insulating material'haying its walls weakenedlat' various places, and a-coverinclosing said'tubqsubstantial-ly asdescribed g; j Q j i 2. A conduit for electric-wires eompri sulati-ng material; havingj alplurality'ofi entering the same providing tongues, and a fabric cov er' over saidtube and over said 7 tongues fielding said tongues upon the main part of the: tube, substantially as described. 5; --Aqconduiti for electric wires comprising a s irally-woundstri of paper having a pluraliiypfi euts extending from edge to edge of the-strip, and a fabric cover over said strip,

substantiall as described. 7 g

6 A con for electric wires comprising an innertube made of a spirally-wound strip ,of material having its walls weakened at a pluralit of places, anda cover inclo'sing said tubegsu, stantiallya's described. 7; conduit comprising a suitablecovering, a arranged therein fcornpos'ed eta strip of suitable material arranged'in'a spiral form and weakenedat "various places, -=wh ereby a pull upon said lining willcause the latter to separate at the weakened points instead of at the joints of the-spiral.

Ai- LUTZW 5 RENCE 0. sIBLEY.

Witnesses: I: x I

Famous- B: R on'lxrms, 

